Am I fat? And how can I loose this chub?

first things first i love that you said chub thank you and your young your thirteen your body is just starting give it time and trust me it aint fat at all what you can do is dont max out with weights but lift weights and skating doesent mean crap neither does riding a biike you need to do things like basket ball or football soccer boxing. just take things in stride really your only thirteen. and i cant say avoid junk food but replace it.